I am way behind in staying up with this thread, but I can’t help responding. What a great post and your father is very lucky to have you. As we grow older we change. You will too. I’ve noticed older folks succumb to peer pressure maybe to a larger degree than all of us did as young teens. When I look at some old photographs, I say what a fool. Some, not all of elder political lunacy can be attributed to this.
One thing to consider in attempting to understand some actions of our loved ones, is that as they grow older their fear of death often decreases. Just this one psychological change alone, results in subtle or sometimes confusing reactions to current situations. I feel so blessed that my parents managed to raise me even though their worldview was so much different from mine. They gave me what I needed most...love, support, and sometimes direction. This is just what the elderly need.